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High power low frequency transmitters was Re: Concrete materials can act as a shorted turn
Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>
At 02:23 PM 1/21/2003 -0700, you wrote:
>Original poster: "James Brady by way of Terry Fritz <teslalist-at-qwest-dot-net>"
>Why did the NSS have a coil room? What where they planning on doing with it?
>Why did they need that much power?
Same reason that VLF nav systems like Omega use loading coils. The antenna
is physically short (in terms of wavelength: 10 kHz>30 km wavelength), and
looks like a big capacitor. You need an inductance to tune the capacitance
That small antenna (a few thousand meters long and a thousand meters high,
in some cases, like the one strung across a fjord in Norway, or the one
across a canyon on Kauai..) isn't a very efficent radiator, so you need a
lot of watts into the antenna to radiate just a few into the air/earth.
Do a web search for Omega Navigation Transmitter to turn up some
interesting stuff. Compared to these guys, we in the TC business are mere
And, compared to AM radio broadcasters at 500-1500 kHz, we are also feeble:
A whole web page about WLW..http://www.ominous-valve-dot-com/wlw.html - "...
Transmitter logs were pretty exciting reading, telling of antenna-house
fires, hurried repairs on still-dangerous circuits, and rushed replacement
of various melted or exploded parts." (sounds like tesla coiling to me...)
http://www.oldradio-dot-com/archives/hardware/WE320A.htm has a description of
the mighty WE320A, which some of you may covet for that truly big tube
coil..18 kV-at- 15 amps on the plate.
"Continental Electronics has delivered AM transmitters at the 2 Megawatt
level to the broadcasting organizations of several countries. It is
reported that several fought a tendency for this level of RF power to melt
and fuse the insulators and sand around the tower."
"Longwave - Radio Luxembourg is said to run a 2 Megawatt transmitter on
Getting closer to typical tesla coil frequencies:
According to WRTH-2000 the following stations transmit on 153 kHz:
Bechar, Algeria 1,000 kW
Bod, Romania 1,200 kW
Donebach, Germany 500 kW
Taldom, Russia 300 kW
Ufa, Russia 300 kW
Komsomolsk, Russia 1,200 kW
Ashgabat, Turkmenistan 500 kW
And of course, though most of these use tubes, there are some solid state
transmitters in this power class:
"s2one specializes in DTV, but we also have expertise in analog TV and
radio servicing. In fact, our past work history includes servicing the
world's first solid state, 1 megawatt AM transmitter."